Sad, sad story, so I better give you all a laugh at my expense to maybe brighten your day. This is the story of the Hera (euro version) that would not steer on launch....scary. I posted my problem to the list some months back and got a lot of useful and helpful responses, but no-one guessed the real reason...it was just so stupid and obvious. First, a bit of history. I have flown this plane in comps for over 2 years, placing well and have been really happy with it, except for the launch. If it went off line, using the rudder did not help. I had to use aileron, rudder and a bit of down elevator to get her back on track - losing valuable launch height every time. I thought the pushrods were flexing, so I tried strengthening them, but to no avail. I also though my flying skills were pretty bad - I had real trouble keeping her smooth when scratching for lift and I could not master rudder-only turns. After a bad round at a comp a couple of months back, my timer (a fellow Hera owner) took a look at the plane. He did a ground check and asked me to put in full left rudder (have you guessed yet?). No, he said, I want 'LEFT'....duh...I had the V tail rudders mixed backwards!!! I switched them over and guess what....she steered fine on the launch. I could not believe it - how stupid can you get? No-one believes I flew for 18 months like this. I can't explain how I did not dork it in on launch. I can only guess that the pull on the line counteracted the wrong rudder commands. I also flew it with aileron-rudder mixed at about 30pc...that explains why I could not fly in accurately in those low thermals. This shows how good the Hera is....even an idiot can win with one! PS: I just got promoted from 'sportsman' to 'masters' in my club after my last win....maybe I will be the first to be demoted after this post! -----Original Message----- From: dave [mailto:[EMAIL PROTECTED]] Sent: Monday, September 04, 2000 12:56 PM To: [EMAIL PROTECTED] Cc: [RCSE} Subject: Re: [RCSE] Hera post crash analysis (long) Dave I don't have this particular aircraft although a Club Mate (now in the US had one and I have been flying moulded models for about 5 years, ( Starlite in the UK). In response to your points at the end of your mail:- 1. Each plane will be slightly different as you say but from experience not enough to cause the sort of problems you encountered although pilot difference is of course an unknown. 2. Unless you've got a very heavy example this just isn't true Phil used to launch his no problem from a decent Hi-start and a gentle chuck. 3. Moving the hook forward would definitely have slowed the climb 4. Moving the CG back would have made the model more squirrely in normal flight as well as changing the launch characteristics. What worries me is that as you say you had the right flap servo buzzing at one point and the model kept turning right whenever you moved the flaps. Are you absolutely sure that this joker was really working properly as if this didn't move down as far as the left one when under flying loads right turn would be an understatement. Phil who had one of these ( my old club mate ) is on this list maybe he'll have some more thoughts. Dave In message <[EMAIL PROTECTED]>, David A. Malone <[EMAIL PROTECTED]> writes >This is by no means meant to reflect negatively on any person, >manufacturer or plane. Learning about why a crash occurs allows us to >become better builders/pilots. Pooling our individual experiences >allows the entire sport to grow, changes can be made to improve designs >and techniques can be enhanced through knowledge. That, I >believe(IMHO), is the essence of this forum. > > I bought a used Hera this year in great shape and flew it with TLAR >settings first. A bit squirrely but definitely showed great potential >and landings were achieved without mishap, albeit a longer distance from >planned. > A post to the exchange resulted in several people graciously sending >me the manufacturer's recommended setup. > I flew the plane yesterday after setting it up to those figures. >Flight Report: >Conditions: Variable Cloudy, intermittent light showers, wind 4-8 and >variable due to storm clouds passing through. > >Setup: per specs with 190 gms of lead in the nose and a 600 mah 4n-600AA >battery. > >Club winch: I'd call it a medium strength one. Older model. > >Prelaunch Check: > > all controls seemed where I set them to > spec. Slight buzzing of right flap servo when Tx was within 3 > feet of servo. The person that built the plane did not twist > the servo leads in the wing nor were there any chokes. > >Range Check: > > Normal > >Launch 1: > > Set flaps to launch settings, checked for surface movement. > Built up medium strong tension on the winch line and gave a > slight forward shove. Immediate Transition to vertical, 15' > up she veered right sharply. Left A input produced no effect, > followed by immediate down E and she came off the tow line at > about 35' up and flew into a right turn, but when I tried to > level her out and get back over the field I seemed to have no > response to left A input, she was still turning right. Then, > thank god, the left A input started to level her out and I was > able to fly her by elevator and rudder control to some high > grass at the edge of the field with no damage done. What was > wrong? I had set the A-F mix at 30% for normal/launch (non > crow) flap control on the left stick. with the left stick all > the way down, I had neutral on all surfaces. Full up on the > left stick was giving me Flaps set to spec at 12 mm for > launch and 5 mm of down ailerons per spec. With the left > stick down, full up trim would give 3 mm flaps for thermaling > and full down would give me about 1 mm reflex. > >The problem! > > with the A-F mix at 30% and the launch flaps set, I had almost > no aileron travel. Now I realize that at the vertical > transition during launch, there is very little aileron control > anyway due to the plane trying to build airspeed so I was in > double trouble. Possible fixes were to eliminate the A-F mix > and/or move the tow hook forward to slow the vertical > transition till the plane had a bit more forward speed. I have > always been taught to only change one thing at a time so I > opted to eliminate the mix first. Not having any A' control at > low speed was very disconcerting. > >Launch 2: > > Straight up the wire until she started to transition back to > level then the ailerons were too touchy and I overcontroled > and came off at about 200 ft. Hands off she was flying nose > up, slow and near stall. It took three clicks of down elevator > trim to get her into a consistent glide and still needed down > elevator when turning upwind and up elevator turning upwind. > Turning rate was very slow with adverse yaw. I did a short > dive and a loop to check for wing to wing incidence and she > came right back to bottom with no drift off line. Brought her > into approach leg and tried adding flaps and she (not crow > yet) and she ballooned up about 6-8' (so she would need a bit > of down elevator mixing there. I did have the elevator mixed > in for crow but not for normal flap control), and looked like > she was setting up a stall so I raised the flaps back up and > she seemed to glide forever but landed safely in the tall > grass again. > > Checking with a more experienced club member, we decided to > increase the up Aileron travel about 2 mm each and to add a > bit more Rudder mix to the Ailerons. > >Launch 3: > > up the wire straight again after the vertical transition and > then got real good height with a short zoom and found the > aileron response much more positive. Tried crow at height and > she seemed to slow nicely without ballooning. She seemed to be > dropping the inboard wing too much on turns so I made a mental > note to reduce out the increased rudder-A mix. > >Launch 4: > > Did not change the settings as a squall line was organizing > on the horizon. the wind and shifted around to the left side, > not real strong ( had handled much worse cross winds with > other planes) Thought she could use some extra lift due to the > wind change so I put the launch flap on again. DISASTER!!! > Instead of tracking straight she veered hard right and this > time down elevator did not pop her off and she plowed in hard > on the right wing tip and nose. The tail broke off totally, > saving the ruddervators. The fuse snapped in half under the > wing. the mid wing section folded near the centerline and the > left tip split open on the leading edge and creased the bottom > panel about 3 inches back from the leading edge (might be > repairable but would never be as strong as it was, nor as > light). > >Conclusions (open to comments, correction or advice) >1) Characteristics of individual planes vary and factory specs require >modification to fit plane, winch and pilot. > >2) This plane requires a strong (fast) winch and a strong throw to get >the airspeed up quickly. (advise from Mike P) > >3) The tow hook could have been moved forward 1/4". and/or > >4) the CG should have been further aft. > >Input appreciated-- Dave Malone > >"All change presents the opportunity for improvement" > >RCSE-List facilities provided by Model Airplane News. Send "subscribe" and >"unsubscribe" requests to [EMAIL PROTECTED] RCSE-List facilities provided by Model Airplane News. 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